How the iter_swap() can be used in the C++

[Tailor]

hello, I am the student of the BscIT. I have to submit the Project on the C++ language in two days. i can have the good knowledge of the functions that can be used in the C++ language. Apart of this, I can not know anything about the iter_swap() function of the C++ language. So, I want to know about the iter_swap() function of the C++ language. I also want to know how can I used the iter_swap() function in the C++ language.

[Praetor]

Hi, The iter_swap() function can be used in the C++ language to an exchange the values of an objects that can be pointed by the two iterators. The following can be the general syntax of the iter_swap() function in the C++ language :

template <class FrwrdItrtr1, class FrwrdItrtr2>
  void iter_swap ( FrwrdItrtr1 p, FrwrdItrtr2 q );

[Katty]

The following program can help's you that how to use the iter_swap() function in the C++ language :

#include <iostream>
#include <algorithm>
#include <vector>
using namespace std;
int main () 
{
  int mint[]={10,20,30,40,50 };   
  vector<int> mvctr (4,99);        
  iter_swap(mint,mvctr.begin());    
  iter_swap(mint+3,mvctr.begin()+2); 
 cout << "mvctr contains:";
  for (vector<int>::iterator t=mvctr.begin(); t!=mvctr.end(); ++t)
    cout << " " << *t;
  cout << endl;
  return 0;
}

The above code can generate the following Output :

mvctr contains: 10 99 40 99

[kelfro]

The iter_swap() function of the C++ language can assigns the content of the argument *p to *q and the content of the argument *q to *p. The behavior of iter_swap() function template can be similar to the following :

template <class FrwrdItrtr1, class FrwrdItrtr2>
  void iter_swap ( FrwrdItrtr1 p, FrwrdItrtr2 q )
{
  swap (*p, *q);
}

[Zecho]

There can be the one more example on the iter_swap() function of the C++ language :

#include <iostream>
using std::ct;
using std::endl;
#include <algorithm>
#include <iterator>
int main()
{
   int b[ 9 ] = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
   std::ostreamiterator< int > otpt( ct, " " );
   cout << "Array a contains:\n   ";
   std::copy( b, b + 9, otpt );
   std::iter_swap( &b[ 0 ], &b[ 1 ] );
   cout << "\n Array a after swapping b[0] and b[1] using iter_swap:\n   ";
   std::copy( b, b + 9, otpt );
   cout << endl;
   return 0;
}

 Output :
Array b contains:
   1 2 3 4 5 6 7 8 9
Array b after swapping b[0] and b[1] using iter_swap:
   2 1 3 4 5 6 7 8 9

[absolute55]

The iter_swap() function of the C++ language can be comes under the Algorithm Header Files. The iter_swap() function algorithm can exchanges the two values in the two locations.

Syntax:
    #include <algorithm>
    void iter_swap( frwrditrtr p, frwrditrtr q );

Whenever the iter_swap() function can be called then the iter_swap() function can exchanges the values of two elements same as that of when you called the function :

swap( *p, *q );